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First, I strongly recommend that you use foreach instead of the for loops you show, it will be much easier to read and write and will be more efficient too. For example:
foreach( lpp cv~>lpps
printf("Name: %s, Purpose: %s\n" lpp~>layerName lpp~>purpose)
As to why you get lots of 'nil' in you last section, it is because a figure will not have "lpps", that is a cellview attribute, rather a figure will have "lpp" which is a list of layer and purpose, and not an LPP object (which is what lpps is).
Hope it helps!
In reply to skillUser:
In reply to ToMWUT:
Not sure if you really need to go via the nets or not. As for tutorial, I'm not sure there is one - although this is covered quite well in the standard Cadence SKILL Programming course - see the "Support & Training" link at the top of this web site...
You can also read the "Design Framework II SKILL Functions" manual - this covers the database in some detail.
I've changed your code a bit, to show some slightly different information - using foreach() as Lawrence suggested (you shouldn't use nth() to access lists in a loop, as lists are sequentially accessed, rather than random access, so it can be slow with long lists). You may find this code useful:
printf("\nALL LPPS (Layer purpose pair) \n")
; Here I want to check what LPPS I have in my design
printf( "LPP name: %s purpose %s \n", lpp~>layerName lpp~>purpose)
printf("\n Figures belongs to LPPS \n")
printf( "LPP name: %s purpose %s \n", lpp~>layerName lpp~>purpose)
printf( "Shapes on this lpp are: \n")
;; could look at whatever you want.
In reply to Andrew Beckett:
Thank you Andrew for your
In fact I will check if
this code will give me any results:
But the problem is that I
already have a SKILL application whitch uses and I have to use this
The quiestion still
remains the same: why while listing all LPPS from CellView, there is
no problem, but when I use: cv~>nets~>figs~>lpp the result
My guess is that you don't have any connectivity in your layout database - if it's just shapes, then there may not be any connectivity, or there may be connectivity, but no routing on those nets - so no figures on the nets. Very hard to tell without knowing what your data looks like.
Easiest to break down using cv~>nets then cv~>nets~>figs (just type it in the CIW to see what you get).
Thanks once again Andrew,
You where right about two
things: first of all you're right that you don't have any data about
my design, so I've decided to put a screen shot with it, so you can
have a look.
This is a very simple
design which was extracted from layout using Assura extraction tool.
This is a NAND cell.
The second thing about
which you were right was that I have a problem with routing, because
when I execute:
cv~>nets~>figs I get
But the problem after the
extraction process is that you can actually see the nets on the
layout, so I have no idea why the Cadence data base has no
information about the figures...
So, no ideas huh guys?
I'm not sure what you mean by "seeing nets on the layout". Cadence has net objects and figure objects (paths, rectangles, etc) but if the net information is not attached to the figs, then cv~>nets~>figs can return nil. Select a shape in your layout and see if it has "connectivity" by querying it. If there is no connectivity on the shape, then the shape doesn't have net information.
In reply to dmay:
Thank you for your reply
I've checked what you've
suggested and it seams that you were right, when put sth like this in
result was also nils. But I have shapes in my design, because when i
I get true as a result...
However I still don't have
any idea why, when the connectivity on the layout seams to be ok,
Cadence Data Base... has such strange data about my design...
I remind you that, SKILL
reports that I have actually nets in design using
Apologies for not replying sooner - I've been travelling visiting customers and there are only a finite number of hours in the day ;-(
Anyway, if this view was created by Assura extraction, it's possible that there was no saveInterconnect() in the rules and perhaps just copyGraphics() statements. Or it may be because you've done RC extraction, and so there are no actual shapes left (all the shapes have become resistors - I've not checked to see what it looks like as I'm in an airport right now).
Anyway, it's not really clear what you're actually trying to check, so perhaps if we knew that we could make other suggestions (although I think I already did that earlier?).
I've checked in various cases I have, and if R, RC, or C only extractions are done, I always have figs on the nets.
But as I said, it might be how the extract rules are written in your case. It's hard to tell without seeing the data. Can you log this via your normal customer support channel into Cadence, as it would probably need more detailed analysis than can be done in a public forum such as this.
I'm still not entirely sure what you're actually trying to check on the extracted view? (You didn't say that in your previous post)
Thank you once again for
I don't know really
what do you mean by: “normal customer support channel into
Cadence”... Because I'm not owner of a Cadence
software I only use it at my University. Could you put here a link,
The second thing is
about the extraction rules in Assura. The problem is that I don't
know what data I could put here to make the things a little more
clearer. Of course I assume that by extraction rules you meant
something which is set in here:
So I've found this
directory in my file system but it has lots of files and I don't
really know where to look.
You also asked me
what I'm trying to check on my extracted view. As I said earlier –
I have an application in SKILL which uses extracted views and object
cv~>nets~>figs to do some calculations, but in this case the
application does not work because there are no figs on nets...
Any suggestions guys :)
Apologies for not replying sooner. As it was the weekend, I wasn't working...
I can't check this particular technology, because I don't have access to it. I wonder whether your University gets its software and technology access via EuroPractice? If so, you can get support via www.europractice.com .
Other than that, you should look at the extract rules (as specified on the LVS form, not the RCX form) and see if copyGraphics is being used rather than saveInterconnect. That said, I'd expect the pin figures to be present at least, so are you sure you got the right cellView? What does cv~>libName, cv~>cellName, cv~>viewName show -is it the right view?